This invention pertains generally to the art of plastic pails and more particularly to plastic pails having metal bail-type handles. The invention is particularly applicable to plastic pails which are subjected to loads or forces at low or freezing temperatures, and will be described with particular reference thereto. However, it will be appreciated that the invention has broader and more general application, and may be advantageously employed in other environments.
Plastic pails of the type to which this invention pertains ordinarily include metal bails that are joined to the pail by means of pliable bail ears or lug members. These metal bails are often wire-like and are bent or formed into a variety of configurations. These configurations are typically governed by either the intended use of the pail or the manner in which the pail is manufactured or assembled.
Of particular interest in the present case are those pails which have integrally molded bail ears of box-like configuration, with an outer face or bail receiving wall of each bail ear having an aperture or bail connection location through which an end of the bail is received. Although these pliable bail ears function adequately at room temperatures, the plastic from which they and the pail are molded sometimes becomes brittle at low temperatures. Because the pails are often used to store frozen food products such as ice cream, it is not uncommon for them to be exposed to prolonged freezing temperatures. When, as a consequence of such low temperature exposure, the plastic becomes frozen and brittle, many configurations of metal bails can cause a rupture or fracture in the outer face of the bail ear, which then allows the bail end to extend further inwardly to puncture a hole through the pail wall. Bits of plastic can then fall into the pail interior and contaminate the food product contained therein. In order to prevent such food contamination, and further to maintain a relatively durable pail, it is desirable to develop a bail ear that offers greater rigidity than the bail ears of the prior art, but to do so without incurring the costs of changing the chemical composition of the plastic from which the combination is molded, or extensively modifying the manner in which the bail end is joined with the bail ear. It is also desirable to develop a corresponding bail member which is not likely to break through the pail wall, while at the same time having such a configuration to allow for ease of manufacturing and assembly of the finished pail product.
In the past, many attempts have been made to overcome the problems described above, and provide an integrally molded plastic bail ear which would prevent a metal bail from puncturing through a plastic pail side wall at low temperatures. For example, integrally molded bail ears of the prior art have included a plurality of rigid support walls extending from an outer surface of a pail wall. Such walls were generally parallel with each other, and extended substantially perpendicularly from the outer wall of the pail. That is, each of the support walls substantially defined a right angle with the pail wall.
There were problems with this attempt. First, when the bail ear was formed so that only two rigid support walls were molded therewith, the bail handle continued to break though the pail wall at low temperatures. As a result, plastic pieces fell into the pail and contaminated any frozen food products stored therein.
Second, when the number of integral walls was increased to four, the two additional walls were positioned parallel to, but inward of, the first two connecting walls. It was intended that any forces applied to the bail ear would be spread along a large area of the pail wall outer surface. The problem with adding walls was that the bail did not have enough space to freely rotate. The vertical length of the additional walls was shortened to accommodate the bail ear, but the bail ear continued to rupture in response to loads at low temperatures. When the bail ears were exposed to low temperatures, the rigid support walls failed to provide adequate support for the bail ear. The right angles defined by the individual support walls and pail wall provided weak, brittle stress areas susceptible to breakage. For instance, when the bail ears discussed above were forced inward toward the pail as a result of high lateral loads, or simply as a result of carrying the pail by the bail, the bail ears tended to break at their weakest points. The bail was thus able to puncture its way through the pail wall and contaminate any pail contents.
Bails of a variety of configurations were used in association with many of the above-discussed bail ears. For instance, bails having knobs at their extreme terminal ends were used. These, however, readily punctured through the pail walls in response to laterally applied forces. Bails with simple J-shaped ends were also used, but these, too, readily pierced through the pail wall. Further attempts at improving the bail included placing a plurality of bends in the bail, both near and at the terminal ends, as well as along the main body of the bail. The presence of these bends provided problems because the pails were difficult to assemble. Not only was it difficult to position the bail in the bail ear, but bails bent along their body portions were easily caught in the assembly machinery. Moreover, many bails of the prior art were configured so that it was difficult to pivotally move them within the bail ears.
The present invention contemplates a new and improved arrangement which overcomes all of the above described problems and provides a rigid bail ear for receipt of a metal bail on a plastic pail. The rigid bail ear of the invention is integrally molded with the pail and provides an economical means for protecting the pail wall from rupture, and for preventing contamination of food or other contaminants contained within the pail. The improvement allows the chemical composition of the prior art pail to remain unchanged, and also greatly reduces the likelihood of bail ear or pail fracture when the pail is exposed to forces at low temperatures. The invention further provides a bail member having a suitable configuration for use in association with the bail ear of the present invention. The configuration reduces the likelihood of the bail piercing through the pail side wall. It also is suitable for ease of pail manufacturing and assembly.